The Abbott government has copped a hiding from voters in two major opinion polls taken after last Tuesday’s budget.

The latest Newspoll, published by the Australian late on Sunday evening, puts Labor ahead of the Coalition on the two-party preferred measure 55% to 45%. Newspoll also recorded the Coalition’s primary vote post-budget at 36% – its lowest level since Tony Abbott took the Liberal leadership from Malcolm Turnbull in 2009.

Newspoll had the Greens dropping three points post-budget to 11%, and a surge to the Palmer United party. The PUP, referenced in the “other” category, polled a substantial 15%.

The prime minister also took a personal hit – his satisfaction rating fell five points to 30% and his dissatisfaction rating rose to 60%, the highest since September 2012. Most voters asked by Newspoll believed the budget left them worse off.

The new Nielsen poll in Fairfax Media publications has the Abbott government in similar territory, with Labor opening up an 11-point lead. Labor is on 56% two-party preferred, and the Coalition on 44%. Nielsen also showed a two-point bounce to Clive Palmer.

Tony Abbott’s personal approval rating dropping by 21 points. Most respondents thought the budget made them worse off, and more than half – 54% – thought the budget would not be good for the country.

The Coalition’s poor poll showing post-budget continues an exceptionally weak opening sortie for the Abbott government. Poll-of-poll analysis covering the seven months since the election suggests the new government has clocked up the weakest federal debut in over two decades, and now voters have given the Coalition’s economic direction a significant thumbs down.

The polls will worry an already nervous backbench. The government’s internal discipline fractured in the difficult weeks leading up to the budget, with MPs publicly questioning decisions confirmed in Tuesday’s economic statement, like the deficit tax and the restoration of indexation on fuel excise.

Abbott was asked about the budget’s multiple broken promises on the ABC, but attempted to rationalise the gap between what was said to voters pre-election and what has happened after it as people “hear(ing) different things".

The prime minister continued to blame Labor for the government’s decision to break its key election commitments, and said it should have been obvious to voters that an austerity budget loomed once the Coalition secured power.

“We constantly talked about Labor spending like a drunken sailor. It was always obvious that we were going to have to rein back unsustainable spending,” the prime minister told the ABC on Sunday.

“We constantly talked about Labor indulging in a cash splash with borrowed money and now we’ve done what is necessary,” he said.

Abbott said the government could have “continued to try to fool people and say, ‘you don't have to change’, but that would, frankly, have been pretending to people that our country could somehow go on living on borrowed money.”

Asked about the dire polls, Abbott told the ABC on Monday, "in the end my job is not necessarily to win a popularity contest, my job is to run the country."

When asked whether he would change strategy in response to the backlash he said, "No, because there is no alternative to get Labor’s debt and deficit disaster under control."

But Abbott has washed out of this critical period publicly at odds with the premiers, who are demanding a special Coag meeting to resolve a dispute over cuts to health and education funding, and also with the Senate crossbench. Labor, the Greens and Clive Palmer are vowing to resist measures like the co-payments for medical services and changes to pension payments.